Because the molecules from which they are made have one end containing a phosphate group that "likes" water and a tail end made from a fat (a lipid) that "hates" water.
phosopholipid
The cell membrane controls what goes in and out of the cell. It is a selectively permeable barrier that allows certain substances to pass through while preventing others from entering or leaving the cell. This helps maintain the internal environment of the cell.
cell surface membrane cell surface membrane
The membrane is inside the cell wall, and its just called the cell membrane.
The outer boundary of a general animal cell is the cell membrane.
Lipid bilayer is composed of two layers of fat cells organized in two sheets. It is typically about five nanometers thick and surrounds all cells providing the cell membrane structure.
its the cell membrane - not to be confused with the cell wall
the cell membrane
The outer covering of a cell that controls what enters and leaves is called the cell membrane. It acts as a barrier to regulate the passage of molecules and ions in and out of the cell.
The outer coating of a cell is called the cell membrane. It is a thin, flexible barrier that surrounds the cell and controls the movement of substances in and out of the cell.
The membrane that surrounds the cytoplasm in a cell is called the cell membrane or plasma membrane.
The membrane that separates one cell from another is called the plasma membrane or cell membrane. It is a phospholipid bilayer that regulates the passage of substances in and out of the cell.